NoClassDefFoundError Could not initialize class EMFService - google-app-engine

I have imported a an app engine project in my eclipse.It was running fine on my previous laptop, here i have copied the eclipse directory from my old machine and imported the project in it. Now I am seeing an error "java.lang.NoClassDefFoundError: Could not initialize class sharepro.java.dao.EMFService" . The error is in line "EntityManager em = EMFService.get().createEntityManager();". I have all the jars added. any pointer on whcih jar I am mising or any conf issue??
Thanks and Regards
Sundi

I realize this is an old post, but I just had this exact problem, and it took me a couple of hours to figure this out today (June 2013). I'm still not sure why my solution worked out (or rather, why my situation was causing the error), but this is what I did to fix it:
I had a source folder in my project structure with a /test folder, where I had some JUnit stuff. I deleted that folder, and now everything works. Weird.
Other things that I saw people suggest for this problem include the following:
Make sure you have copied the appropriate .jar files into your /war/WEB-INF/lib folder
Make sure you're not calling your EMF singleton from client code (if you're using GWT)
Make sure you have enabled the Datastore option for your project (Project Properties > Google > App Engine > Datastore > Use Datanucleus JDO/JPA to access the datastore)

(I know this is an old post but in case anyone else needs help)
Your error is more than likely in your JDO, I just had this problem, I didn't annotate a JDO properly and I got the same error as you did

This is because enhancer does not properly enhance your entities. You should enhance entities.

Related

Google App Engine Error: DNS lookup failed for URL: http://metadata.google.internal

I've been working on a small Google App Engine (standard environment) project that uses Cloud Endpoints v2. My code is largely based on the quickstart provided by Google.
Everything was working fine, but I re-deployed today after having not looked at it for a few weeks, and I'm getting the following error when I attempt to call the endpoint:
error: An error occured while connecting to the server: DNS lookup failed for URL: metadata.google.internal
This wasn't happening before. It seems to be happening when the endpoints package is being imported by Python.
My endpoint doesn't do anything fancy - I haven't changed the source from the sample EchoApi. The error ends up in the GCP Logging console no matter if I try to access the API through the API Explorer or via Curl.
I don't get any errors during deployment.
Edit #1
Some further information:
The error originates from within Google's code that is included with the google-endpoints package which I've included in my lib folder, per
the documentation. Specifically, the error occurs on line 54 of google/api/control/wsgi.py.
Basically, it's making a request to metadata.google.internal using urllib2.
I'm guessing this address is only available from within the Google Cloud, and that for whatever reason, the instance that's hosting my app can't do a DNS lookup on it.
Edit: #2
Dug a bit further.
It seems that the error originates in the google-endpoints-api-management package. Changes committed to that package on October 19th seem to have introduced additional platform reporting. metadata.google.internal is queried to check if the code is running within the Google Container Engine, then it blows up, because the metadata address doesn't resolve.
Here's the commit:
https://github.com/cloudendpoints/endpoints-management-python/commit/0a37d0e443091053ed03e455e06d3a0ae770999f
The google-endpoints package only requires google-endpoints-api-management >=1.0.0b1. On my end, things were working fine on version 1.0.0b2, but then I built a new lib folder, which brought down 1.0.0b5, and things went sideways. Required packages haven't changed between b2 and b5, so I'm thinking I may be able to just downgrade back to b2 for the time being. Haven't tried it yet.
Sent the Google Dev an email. Perhaps he'll chime in with further tips.
Edit: 2016-11-07
Tested downgrading the google-endpoints-api-management package to 1.0.0b2. Seems to be working, kludgy a fix as it is. If you're using the lib folder, the following will scrub the newer error-prone wsgi.py file and put back the older one:
pip install -t lib google-endpoints-api-management==1.0.0b2 --upgrade
Not pretty, but it may just get you back in business.
On a side note, the Google engineer promptly replied saying that he would take a look at this issue soon. With luck, endpoints v2 will eventually come out of beta, 'cause I'm really liking it so far.
This will be fixed in an upcoming patch to the google-endpoints-api-management package (which will be 1.0.0b6). It will probably be released sometime on Monday, 11/6.
If you'd like to continue testing right away and this error is blocking you, you can go back to 1.0.0b4 until 1.0.0b6 comes out. Everything should still work as normal with that version.
Thanks for bringing this to our attention! We're doing our best to iron out all of these wrinkles now during beta in preparation for our first general release.
EDIT: 1.0.0b6 has been released and resolves this issue. Thanks for your patience during our beta phase!
(Posted solution on behalf of the OP).
Google has released version 1.0.0b6 of the google-endpoints-api-management package to address this issue. It solved the problem for me. For anyone who is encountering this problem, clean out your lib folder and re-install the google-endpoints package. This will bring down the new google-endpoints-api-management package with it.
Thanks to Brad at Google for really quick action on this.

Updating AppEngine deployed version on GitHub push

Is it possible to auto-deploy to AppEngine when Github receives a new commit? I found a bunch of dead documentation links that suggest it is, however I still have no idea how to set it up. There are some mentions for creating a release pipeline, but I don't see any way to do that in the cloud console anymore.
I've got my code mirroring the GitHub repository already, however I can't figure out how to link this to the deployment pipeline or even how to create a new version. Am I missing something obvious? This seems like it should be incredibly straightforward to do...
The entry on the Google Cloud Platform blog that's supposed to explain how to achieve this is blank. It seems Google quietly killed this feature. Some people have complained that it suddenly stopped working. The only way to do this now is to use Continous Delivery/Integration tools such as Travis CI.

gwt sample project rpc call failure

When i try to run gwt sample project it gives "RPC call failure.An error occurred while attempting to contact the server. Please check your network connection and try again". It was running good before but after i update programs and libraries it gives that error. Which update causes this error or there is other things?
Appengine version:1.7.0
GWT version:2.4.0
Eclipse version:4.2(juno)
JDK version:1.7.0_05
This may not be the problem you are facing but it seems to be the most frequent problem.
Let me predict - you last tried GWT four years ago and you hoarded the sample project hoping to pull it out one day.
And yesterday, you did pull it out. It kinda worked and then you decided to upgrade to the latest 2.4.0. (Actually the latest is 2.5.0-rc1).
Ooops. The web-inf/lib of your project is still faithfully using pre-version 2.2 gwt-servlet jar.
Nope, you can't do that. GWT-RPC data transfer format is version-unstable. Not guaranteed to be compatible from one version to the next.
Simple solution - recreate a new GWT project using the new Google plugin.
Then copy the src and web.xml of your project into the new project.
Or replace the gwt-servlet.jar with the latest. And if you usegwt-servlet-deps.jar, you would need to upgrade that too (but I doubt so, because if you did use gwt-servlet.deps.jar you wouldn't be asking this question).
But why would you keep the gwt sample from an old project?
The samples have remained quite the same over the years. Why not use the samples from the new GWT 2.4.0 download. You don't have to keep the samples. You should try to construct the projects for the samples afresh.
The GWT directory is found under Eclipse's plugins directory, under a long name. Like
plugins/com.google.gwt.eclipse.sdkbundle_2.4.0.v201205091048-rel-r37/gwt-2.4.0.
In which you will find the samples directory.

My GAE python development datastore is never persisted to a file

I have just started using GAE (Python 2.7 SDK 1.6.4) , I have set up a
simple test project using Pydev (latest version) in eclipse (indigo)
on Windows XP (SP3).
It all works fine, my app can record data in the datastore and the blobstore
and then retrieve it, but when I stop the development server and start
it again the data in the datastore is lost. This is not the case for
the blobstore which is retaining blobs fine and I can see the
blobstore folder that gets created in C:\Temp
I did the sensible thing and look back through old posts and found
that most people who have this problem solve it by changing the
location of the datastore file, so I used the following parameters;
--datastore_path="${workspace_loc}/myproject/datastore"
--blobstore_path="${workspace_loc}/myproject/blobstore"
"${workspace_loc}/myproject/src"
I moved the blobstore at the same time as you can see.
The blobstore still works, and now the blobstore folder is created in
myproject folder as expected. The datastore file is still not created
however, and when I stop and restart the development server the data
is still lost.
The dev server startup logs include the following entry
WARNING 2012-04-20 10:49:04,513 datastore_file_stub.py:513] Could not
read datastore data from C:\myworkspace\myproject\datastore
So I know it is trying to create the datastore in the correct place.
Finally I lifted the whole eclipse workspace folder and copied it to
another computer with exactly the same setup except it is running
Windows 7 instead of Windows XP.
Everything works fine there - both the datastore file and blobstore
folder are now created where I expect them to be.
I have set up eclipse, python, gae, my project and my eclipse launch
file in exactly the same way on two computers, it works on one and
not the other. Maybe XP is something to do with it but to be honest I
think that's unlikely.
The only other clue I have come up with is that a recent change to the
GAE development server stopped writing to the datastore file after
every change and only flushes on exit, this problem may be closely related to mine;
App Engine local datastore content does not persist
However adding the following to my code did not help at all.
from google.appengine.tools import dev_appserver
import atexit
atexit.register(dev_appserver.TearDownStubs)
So it's not down to incorrect termination sequence either as far as I
can tell although it may be that I was just added it in the wrong place (I'm am new to python).
Anyway I am stumped and I would be really grateful for suggestions you
guys can come up with.
It's probably http://code.google.com/p/googleappengine/issues/detail?id=7244 and a bug. Hopefully a fix will be available soon.
did you try:
--storage_path=...
Path at which all local files (such as the Datastore, Blobstore files, Google Cloud Storage Files, logs, etc) will be stored, unless overridden by --datastore_path, --blobstore_path, --logs_path, etc.
found at https://developers.google.com/appengine/docs/python/tools/devserver?csw=1

is there a way to download my application code from GAE

I accidently deleted my application code from my own machine, however it's running on Google App Engine (GAE), is there a way I could download it from there?
--
app engine actually recently added the ability for the developer who uploaded a given app version to download its source code:
http://code.google.com/appengine/docs/python/tools/uploadinganapp.html#Downloading_Source_Code
You cannot do this unless you have prepared your app ahead of time properly. There is a chance the trick described by Nick in the duplicate question here might work for you. Otherwise, I would suggest using source control like git or svn.

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